The present invention relates generally to agricultural harvesting equipment and more particularly relates to harvesters for root crops such as sugar beets.
When root crops such as sugar beets are harvested, dirt often clings to the root surfaces, particularly when wet or moist ground conditions are encountered during the harvest. To remove the dirt, it has been customary to pass the roots over roll-type cleaning conveyors which in addition to conveying the roots also tumble the roots providing a scrubbing action thereto. Nevertheless, roots harvested during muddy soil conditions often pass over the rolls with enough mud clinging to them to result in a mud buildup around the rolls.
To provide a compact and easily transportable beet harvester, vertical auger conveyors have replaced bulky and wide chain conveyors to elevate the beets or roots from the root cleaning conveyors to a position where they can be conveyed to a truck or trailer moving alongside the harvester. Should the conveyor rolls deliver muddy beets to these auger conveyors, the auger as well as the conveyor rolls after become impacted with mud buildup. Consequently, both of these mechanisms often become ineffective or overly aggressive and thereby damage or crush the beets.
An additional problem frequently encountered occurs when harvesting conditions expose the beet harvester to rocks and other foreign materials intermixed with the beets. Usually the conveying rolls and grab rolls are placed sufficiently far apart to permit loosened soil, small rocks and other foreign material to pass therealong. However, when rocky soil conditions are encountered, rocks conveyed with the beets to the elevating auger may, if of a certain size, become wedged or jammed between the conveyor rolls or auger and its housing, thereby resulting in significant damage to the harvester with accompanying lost or downtime.